Hopefully the question is clear: basically, why is it that water on roads decreases friction, and water on a floor can make it easier to slip, but water droplets on feet make putting on socks harder?
In: Chemistry
Clothes usually don’t fit very tight hence the friction is low. But wet clothes are forced onto your skin by the cohesion of water (that also sticks very well to most fabric) and the atmosphere as the water makes the fabric impermeable to air creating a suction effect. Since friction increases proportional to the normal force wet clothes are much stickier.
When slipping on a wet floor or hydroplaning the cohesion of the water doesn’t change the normal force and hence the friction much because the gravity of the object itself is much greater. Instead on smooth surfaces water fills in all unevenness of the surfaces with a layer in between that can’t transfer friction very well as the shear strength of low viscosity fluids is basically zero. On rough surfaces this effect usually isn’t pronounced enough to actually make you slip but a car can move faster through water on the road than the water can move out of the way increasing the layer of water between the road and tire – if the layer is thick enough you get hydroplaning.
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